"Note:
These data represent prisoners
housed in Federal
Bureau of Prisons facilities; prisoners housed in contract
facilities are not included. Data for
1970-76 are for June 30;
beginning in 1977, data are for September 30."
The 2004 stats in the chart are for November 4.

From
the link just above: State and Federal prisoners
totaled 1,421,911 in 2004. Jails held another 713,990.
The "quick facts" link has detailed stats on race, gender,
ethnicity, offenses, sentences, nationality, total inmates, etc..